CVE-2026-104021 (GCVE-0-2026-104021)

Vulnerability from cvelistv5 – Published: 2026-10-10 04:26 – Updated: 2026-10-10 04:26
VLAI
Title
Fastcache by Host.it <= 1.7.4 - Authenticated (Administrator+) Code Injection via .htaccess Directive Injection via 'cache_cookie_exclude' Setting
Summary
The Fastcache by Host.it plugin for WordPress is vulnerable to Code Injection in all versions up to, and including, 1.7.4 via the `fastcache_settings[cache_cookie_exclude][]` parameter. This is due to the plugin registering the `cache_cookie_exclude` setting via `register_setting()` without a `sanitize_callback`, while `buildSiteHtaccessRules()` applies only `trim()` to each cookie value before interpolating it directly into an Apache `RewriteCond` line — a normalization that strips surrounding whitespace but leaves embedded newlines intact, allowing an attacker to break out of the capture group and append arbitrary directives. This makes it possible for authenticated attackers, with administrator-level access and above, to inject arbitrary Apache directives into the site's `.htaccess` file via `file_put_contents()`, enabling server-level configuration changes such as setting `php_value auto_prepend_file` to execute attacker-controlled PHP code on every request.
Severity
7.2 (High)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-94 - Improper Control of Generation of Code ('Code Injection')
Assigner
Wordfence CNA under the mitre root
CNA scorecard C 65/100 over 2215 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
hostspa Fastcache by Host.it Affected: 0 , ≤ 1.7.4 (semver)
guessed Create a notification for this product.
Credits
Wordfence PRISM
Show details on NVD website
To clipboard 

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        }
      ],
      "metrics": [
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            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
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      "problemTypes": [
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        "shortName": "Wordfence"
      },
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        },
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          "url": "https://plugins.trac.wordpress.org/browser/fastcache-by-host-it/tags/1.7.4/src/Core/Platform/Utility.php#L545"
        },
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          "url": "https://plugins.trac.wordpress.org/browser/fastcache-by-host-it/tags/1.7.4/src/Core/Platform/Utility.php#L521"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/fastcache-by-host-it/tags/1.7.4/src/Dispatcher.php#L480"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/fastcache-by-host-it/tags/1.7.4/src/Admin.php#L73"
        },
        {
          "url": "https://plugins.trac.wordpress.org/changeset?reponame=\u0026old=3735944%40fastcache-by-host-it\u0026new=3735944%40fastcache-by-host-it"
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          "time": "2026-10-09T04:48:48.000Z",
          "value": "Vendor Notified"
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        {
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          "time": "2026-10-09T15:38:40.000Z",
          "value": "Disclosed"
        }
      ],
      "title": "Fastcache by Host.it \u003c= 1.7.4 - Authenticated (Administrator+) Code Injection via .htaccess Directive Injection via \u0027cache_cookie_exclude\u0027 Setting"
    }
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    "dateReserved": "2026-10-01T17:00:05.312Z",
    "dateUpdated": "2026-10-10T04:26:48.359Z",
    "state": "PUBLISHED"
  },
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        "cveTags": [],
        "descriptions": [
          {
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            "value": "The Fastcache by Host.it plugin for WordPress is vulnerable to Code Injection in all versions up to, and including, 1.7.4 via the `fastcache_settings[cache_cookie_exclude][]` parameter. This is due to the plugin registering the `cache_cookie_exclude` setting via `register_setting()` without a `sanitize_callback`, while `buildSiteHtaccessRules()` applies only `trim()` to each cookie value before interpolating it directly into an Apache `RewriteCond` line \u2014 a normalization that strips surrounding whitespace but leaves embedded newlines intact, allowing an attacker to break out of the capture group and append arbitrary directives. This makes it possible for authenticated attackers, with administrator-level access and above, to inject arbitrary Apache directives into the site\u0027s `.htaccess` file via `file_put_contents()`, enabling server-level configuration changes such as setting `php_value auto_prepend_file` to execute attacker-controlled PHP code on every request."
          }
        ],
        "id": "CVE-2026-104021",
        "lastModified": "2026-10-10T05:16:39.503",
        "metrics": {
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                "userInteraction": "NONE",
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              },
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              "impactScore": 5.9,
              "source": "security@wordfence.com",
              "type": "Primary"
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          }
        ]
      }
    }
  }
}



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